This invention relates to buffers, such as buffers for providing isolation.
A circuit design typically includes a plurality of circuit blocks. The testing of the circuit design for functionality can be accomplished by independently testing each circuit block by providing known logic patterns to the inputs of a circuit block and then observing the respective outputs of the circuit block as is understood. However, when more than one circuit block is being tested, a logic pattern used to test a first circuit block may not be an acceptable logic pattern to a second circuit block wherein a valid logic pattern to the first circuit block may cause a failure in the second circuit block. Further, as circuits grow in size and complexity, the logic patterns that adequately test a given circuit block typically become increasingly difficult to generate. Therefore, after generating a test pattern for one circuit block, it would be a substantial hindrance to realize that the test pattern could not be used since it would cause a failure in another circuit block. Thus, when testing one circuit block on a design, it would be advantageous to isolate all other circuit blocks on the design so as to prevent catastrophic failures of the other circuit blocks.
Hence, when testing one circuit block of a circuit design, there exists a need to provide isolation for the other circuit blocks of the circuit design.